The invention relates to air cleaners, and more particularly to air cleaners having a tangential inlet and a precleaner.
Air cleaners with a tangential inlet and a precleaner are known in the prior art. Such air cleaners typically have a cylindrical housing and provide two stage cleaning, namely a precleaner provided by flow from the tangential inlet along a spiral path, and a second stage provided by radial inward flow through an annular filter element. The precleaner is typically provided by an annular sleeve circumscribing the annular filter element and spaced radially inwardly of the interior surface of the cylindrical sidewall of the housing by a radial gap defining an annular flow channel between the sleeve and the interior surface of the cylindrical housing sidewall. A ramp in the channel may direct air flow along a helical pattern. The sleeve also helps to locate and center the annular filter element within the housing. While the sleeve provides the noted desirable functions, it also contributes to restriction of the air flow as it enters the housing, which restriction is undesirable.
The present invention addresses the noted restriction disadvantage, and provides a sleeve which desirably facilitates the noted helical air flow pattern for precleaning and also facilitates location and centering of the annular filter element within the housing, and which reduces entry restriction to air flow suffered by prior sleeves.